Cardiac Rhythm Conduction and Bloodwork

The normal intrinsic electrical conduction of the heart allows electrical propagation to be transmitted from the Sinoatrial Node through both atria and forward to the Atrioventricular Node. Normal/baseline physiology allows further propagation from the AV node to the ventricle or Purkinje Fibers and respective bundle branches and subdivisions/fascicles. Both the SA and AV nodes stimulate the Myocardium. Time ordered stimulation of the myocardium allows efficient contraction of all four chambers of the heart, thereby allowing selective blood perfusion through both the lungs and systemic circulation.

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Blood work

Your Cardiologist will often order numerous blood tests to check if you need to be on medications to help reduce your risk of heart disease by looking at your cholesterol levels, or to diagnose a recent heart attack by looking at your cardiac enzymes. It is important to have your blood work done whenever necessary, and to follow fasting instructions when needed to allow your Doctor to provide you the best care possible.

Electrocardiogram (EKG, or ECG)

An EKG measures the electrical activity of the heart and how well it is functioning. Your heart has something similar to a small electrical generator built-in, which fires electrical signals to the different chambers of the heart at the proper time. When it is functioning properly, the top chambers of the heart muscle (atria) flex first, then the bottom chambers of the heart flex second. This synchronization is very important to properly pump blood through the heart with as little “turbulence” as possible. See Atrial Fibrillation for more information about improper electrical activity.

An EKG can help your Cardiologist diagnose numerous abnormalities. An EKG takes only a few minutes, and requires small sticky pads to be placed on your chest and your arms or shoulders, and your ankles or hips. A small area may need to be shaved for the pad to stick. Be sure to request hypoallergenic pads if you have severe allergies. Wires or leads are attached to these sticky pads, and the signal is sent to the EKG machine to be interpreted. Your doctor will tell you more about what it means.

For a detailed explanation of what your EKG shows, click here

Cardiac SPECT - Cardiac nuclear imaging is also called a "perfusion scan." A small amount of radioactive material is injected into the bloodstream. Then a SPECT camera (similar to CT) images the tracer in the blood as it flows through the heart muscle. The tracer leaves your body within hours. This test can be done in our offices, the entire test will take about 3-4 hours. Download the SPECT Instructions document.

Holter Monitor

The purpose of a holter monitor is to study the electrical activity of the heart over a 24 hour period. It records the heart rhythm continuously to capture electrical abnormalities of the heart (arrhythmia). After the nurse places the electrodes to the skin, the patient takes home a small digital recorder for 24 hours and engages in his/her usual activities (except anything that endangers the monitor such as jumping in water). The patient keeps a diary of any symptoms that occur. The Holter should be returned to our office the next working day so the data can be analyzed. There is no need to prepare for this test, although the nurse may need to shave the area for the patches to be placed if there is excessive hair.

Event Monitor

An event monitor is similar to a holter monitor except that it records for a longer period of time and only reports abnormal electrical activity. It will also record when the patient is experiencing symptoms, which is triggered by a button on the device. These devices wirelessly transmit data to a reading center 24/7, and can have an urgent report to our office in minutes if a serious event has occurred. These devices are revolutionary in the care of our patients and have allowed our physicians the ability to capture an immense amount of valuable data to better diagnose our patients.